Medical and biological engineering

, Volume 14, Issue 5, pp 570–579 | Cite as

Theory of evaluation of the single pneumatic resistor decompression computer

  • R. S. Howard
  • H. Bradner
  • K. Schmitt


The development of decompression meters is historically reviewed. The theory of the popular automatic decompression meter marketed by Scubapro is critically discussed, and it is shown that the meter's time constant varies inversely with dive depth. Thus, the meter is a ‘multitissue’ device. The meter's performance is compared with the US Navy's ‘no decompression limits’. It is concluded that use of the meter by recreational divers should be discouraged.


Analogue simulation Decompression Diving physiology 


Ce mémoire présente l'historique des compteurs de décompression. Le principe du compteur de décompression automatique universel introduit sur le marché par Scubapro fait l'objet d'un examen critique, et l'on démontre que la constante de temps du compteur varie inversement avec la profondeur de plongée, donc que le compteur est un dispositif à ‘tissus multiples’. La performance du compteur est comparée à l'état ‘sans limitation de décompression’ de la marine américaine. On en conclut qui'l s'agit de décourager l'utilisation de ce compteur par les plongeurs sportifs.


Die Entwicklung von Dekompressionsmessern wird aus historischer Sicht betrachtet. Es folgt eine kritische Beurteilung des beliebten, von Scubaprop vertriebenen automatischen Dekompressionsmessers, und es wird nachgewiesen daß sich die Zeitkonstante des Messers im umgekehrten Verhältnis zur Tauchtiefe ändert, so daß der Messer eine ‘Mehrfachgewebe-Vorrichtung’ darstellt. Die Leistungsfähigkeit des Geräts wird mit den ‘ohne Dekompression Grenzen der US-Marine verglichen. Man gelangt zu dem Schluß, daß der Gebrauch dieses Meßgerätes durch Freizeittaucher abgelehnt werden sollte.


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Copyright information

© International Federation for Medical & Biological Engineering 1976

Authors and Affiliations

  • R. S. Howard
    • 1
  • H. Bradner
    • 1
  • K. Schmitt
    • 1
  1. 1.Scripps Institution of OceanographyLa JollaUSA

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